Flexible cartridge or refill for stapling machines



May 1, 1956 H. LERNE R FLEXIBLE CARTRIDGE OR REFILL FOR STAPLINGMACHINES 2 Sheets-Sheet 1 Filed March 17, 1953 LIJ : INVE;OR

ATTO R N EY y 1, 1956 H. LERNER 2,743,445

FLEXIBLE CARTRIDGE OR REFILL FOR STAPLING MACHINES Filed March 17, 19532 Sheets-Sheet 2 ATTORN EY United States Patent FLEXIBLE CARTRIDGE ORREFILL FOR STAPLING MACHINES Application March 17, 1953, Serial No.342,940

'7 Claims. (Cl. 1--56) The present invention is directed to fasteningand specifically relates to an elastic staple element belt or stripadapted to be closely wound on itself into a roll or folded machine gunbelt fashion or foldable into other forms to define a cartridge orrefill adapted to be conveniently loaded in a stapling machine. Oneobject of the invention resides in the provision of a novel andeffective pliable staple element belt formed by a multiplicity ofrectilinear staple elements arranged side by side fashion and secured inthe same rectilinear plane by a resilient structurally stable bond orcoating having an adhesion to the elements greater than the cohesion ofthe coating itself between any pair of contiguous elements thereof.Another object is to provide a serviceable and flexible staple elementstrip adapted to be wound upon itself to form a cartridge having amultiplicity of juxtapositinned rectilinear metal staple elementsindependent of each other, that is, bodily separate from or mutuallyexclusive of each other and disposed substantially in the same plane andhaving a relatively thin flexible synthetic plastic layer common andadhered to the adjacent or contiguous elements of the strip and whereinthe layer or coating has less inherent cohesive strength than theadhesive bond thereof to the elements and wherein the layer formsswinging connections for the adjacent elements of the strip. Anotherobject resides in the provision of a staple element strip of thecharacter referred to wherein the layer is a relatively thin syntheticelastic plastic to characterize resilient and swingable connectionsbetween the contiguous elements of the strip. Another object comprehendsthe utilization of a relatively thin synthetic plastic and flexible filmadapted, to be superimposed on the resilient plastic layer of the stapleelement strip while the layer is still wet to permit prompt winding ofthe staple element strip into a roll to form a staple element cartridgeand wherein the adhesive bond of the film to the layer has an adhesivestrength greater than the cohesive strength of the film. A furtherobject resides in the provision of a flexible and elastic staple elementstrip which is reinforced along the length thereof by the superimposedrelatively thin synthetic plastic film which is elastomeric. Anotherobject is realized in the provision of a' serviceable staple elementbelt that is flexible, deformable, twistable and resilient, neverthelesssusceptible for prompt processing in appropriate die components forbending all of the elements of the belt in one operation to form a stackof resiliently united U-shaped elements, thus providing a staple stackwhich may be subject to distortion, shock, twisting and stretching as inthe case of the elastic belt out of which it was formed without,however, disturbing the effectiveness of this staple stack or theeffectiveness of a cartridge if formed out of the belt after loading inits respective stapling machine. Other important objects and salientadvantages will appear from the following detailed specificationconsidered in the light of the I accompanying drawings wherein:

Fig. 1 is a' fragmentary perspective and broken view of the elasticstaple element belt forming machine.

Fig. 2 is a broken fragmentary view of the machine illustrated in Fig. 2showing the staple belt cutter behind the complementary forming dies forsevering predetermined lengths of belts prior to forming U-shapedresilient staple row or strips or stacks therefrom and by thecomplementary forming dies.

Fig. 2A is a fragmentary view of the elastic belt illustrating thecoated area on the'juxtapositioned staple elements.

Fig. 3 is a perspective view showing the resilient staple element beltwound into a roll to define a cartridge bodily insertable in a staplingmachine.

Fig. 4 is a perspective view of the staple element belt folded uponitself machine gun belt fashion to characterize another type ofcartridge.

Fig. 5 is a perspective view of an elastic stack of staples according tothe invention and produced by the machine shown in Fig. 2.

Fig. 6 is a transverse sectional view on the line 6-6 of Fig. 5, howeveron a larger scale.

Fig. 7 is a perspective view of a resiliently united and compensatorystack of staples of Fig. 5 but shown temporarily deformed and distortedfor purposes of illustration, with one part of the stack swung aboveanother part thereof.

Fig. 8 is a fragmentary enlarged longitudinal sectional view of thestaple element belt taken on the line 8-8 of Fig. 2A illustrating theresilient coating applied.

Fig. 9 is a view similar to Fig. 8 but showing the elastic coatingreinforced by the superimposed elastic tape or film, to define alaminated resilient connection between pairs of staple elements.

Referring to the drawings, straightened metal wire W fed into guideblock GB across guide slot S thereof in any desirable manner andsubsequently appropriately held down by the reciprocating pressure padPP. Thereafter companion nippers N pivoted on pin 10 cut the wire inpredetermined lengths to form rectilinear staple elements SE. This wiremay be substantially rectangular or round in cross section. Aftersevering a predetermined length of wire disposed across guide slot S,ejector plate E is suitably reciprocated by the rocking elbow EL andfeeds thecut off predetermined lengths of Wire or staple elements SEunder throat or gap G continuously filled with a liquid adhesive SLdraining from reservoir or concavity R into the wiper block WB.

. Supply tank T controlled by valve V contains the liquid adhesivemixture SLwhich principally for purposes of example, is a butadieneacrylonitrile copolymer modified with a phenolic resin and plasticizedin a ketone solvent system, such as acetone and preferably methyl ethylketone, the latter being less volatile than acetone although having gooddrying properties and other advantages for storing. This ketone solventsolution renders the buta diene acrylonitrile copolymer fluid. Theresilient synthetic plastic adhesive coating formed from this mixturedoes not require heat, pressure or the use of any catalysts for setting,the above being merely as a representative example and not intended tolimit the scope of the invention. The adhesion of this coating or layerto the wire metal staple elements is greater than the cohesion of thecoating itself between any two staple elements connected by thiscoating. This is especially true where the bonded or joined stapleelements are separated under medium slow to very fast speeds in whichcase because of the character of the resilient adhesive coating appliedthat part of the coating above the staple element to be severed goes orsticks with this severed staple element. Under very low speeds, forinstance, about one inch per minute, the coating of the staple elementto be severed will peel, that is, that part of the coating formerlyadhering to it will] not go with this staple element but will cling tothecoating on the adjacent staple element. Consequently advantage istaken of the character of this resilient coating in that driving bladesof stapling machines operate at rates of speed appreciably in excess ofthe above mentioned medium slow speed and therefore peeling of theadhesive coating above the driven staple is overcome.

The staple elements SE are rapidly formed in the guide slot S and arefed one in back of the other and contiguous thereto in side by siderelation under throat G where they are coated as they pass under thewiper block WB. The feed of the liquid adhesive to the reservoir R andthroat G and thereafter to the staple elements passing under this throatis by gravity. The wiper block WB controls the thickness of the coatingor layer C to be applied, since it is well understood that the wiperblock may be adjusted by any suitable means towards or away from guideblock GB. The coating referred to of course is a continuous syntheticplastic resilient adhesive and its thickness should be approximately.002" and generally satistactory. Manifestly if the thickness of theresilient coating be appreciably increased, the inherent condition ofadhesion being greater than the cohesion will be reversed. The. coatingC spread across the top surfaces of the elements, as well as the groovesor interstices 20 (Fig. 8), formed thereby is disposed along the centralregions thereof, that is, this coating has a width commensurate with thebreadth of the area or zone intermediate the margins M of the stapleelements (Fig. 2A).

After the adhesive coating is wiped on the travelling juxtapositionedelements SE, speedier drying is possible, if the coated staple elementsare passed through a drying chamber TC wherea light vacuum is maintainedby the aid of a conduit P associated with a vacuum pump (not shown). Ifdesired the coated staple elements may now be passed onto the movingconveyor belt CB and severed into predeteringed lengths by theoscillatable knife K appropriately adjusted and controlled by suitablemeans (not shown) to be effective at predetermined intervals as is wellunderstood. It is apparent that an elastic staple belt is formed havinga multiplicity of contiguously arranged side by side positioned andresiliently connected staple elements all in the same plane. But thisbelt SB may be completely rolled or wrapped upon itself and even tightlyabout one end thereof as to leave no core or bore at the origin thereofas illustrated by the cartridge indicated in Fig. 3. Since this type ofbelt is elastic substantially in all directions, being also foldable,flexible and even twistable, it is susceptible to many types ofpackaging, that its, it may take as is well apparent, other forms thaneither a roll as shown in Fig. 3 or the machine gun belt fashion foldedcartridge shown in Fig. 4.

In all instances the wire staple elements of the belt or strip arestraight or rectilinear and the belt after having been formed into itsdesired cartridge or pack may be conveniently housed in a staple formingand staple ejecting machine as is well understood. Brieflyrecapitulating, the dominant features of the staple element belt due tothe resilient bond between each pair of stable elements thereof are asfollowing:

1. The belt may be stretched lengthwise and automatically retracts toarrange the staple elements in their normal contiguous orjuxtapositioned side by side relation.

2. The belt may be stretched relative to corresponding ends thereof toarcuately diverge the opposite corresponding ends and thereafter theelements retract automatically to their normal contiguous relation.

3. The adhesion of the resilient adhesive coating to the staple elementsof the belt is greater than the cohesion of the coating connecting thepairs of staple elements of this belt. If therefore, the coated foremoststaple element of the belt be severed by the driver in a staplingmachine, that portion of the coating above the severed and driven stapleelement remains with and still adheres to the latter when ejected fromthe stapling machine. By such action accumulations of portions of thecoating which would have a tendency to clog the raceway in the staplingmachine is desirably prevented. This action also holds true with a stackof staples according to the invention;

Example I In the first example just discussed, since the mixture SLcontains 70 percent solvent by weight relative to the solids content,the drying action of the adhesive coating or bond, that is, its rate ofevaporation after spreading on the staple elements, although good inproducing an effective elastic staple element belt, is not fast enoughfor practical high speed production even though aided by a dryingprocess. Consequently, a larger drying time interval is required. Insuch case, the staple element forming machine must be run more slowly ora relatively larger staple element guide and conveyor be employed.

Example II To overcome these undesirable factors the adhesive mixturepreviously mentioned is replaced by a fluid solvent in tank T. Thissolvent may be of acetone although preferably methyl ethyl ketone isemployed. in ad dition, a resilient tape F is also utilized. This tapeis made by driving the solvents from a thin layer of the butadieneacrylonitrile copolymer, leaving the solids in the form of film or layerwhich is elastic and flexible and is found up to form roll RL asindicated in Fig. 1 wherein the staple elements SE would be firstmoistened by the solvent and wet, when meeting the tape F which isapplied thereonby the presser roller RR continuously and yieldinglyurged downwardly by springs SG. This film may be said to be a solidelastic adhesive.

By this process the drying chamber TC may be omitted. The conveyor CB ifdesired may also be eliminated and even the staple element guide blockGB may be shortened. The speed of producing the elastic staple elementbelt is no longer limited to the drying time.

Example III A further process is evolved in utilizing a relatively thinplastic film in the form of a tape easily and commercially available.This very thin, generally transparent, plastic film has, as its dominantcharacteristic elastomeric properties and may be rubber hydrochloridealthough not necessarily limited thereto but may be of any other plasticfilm possessing substantially equivalent phys ical properties.

By elastomeric, is meant, flexible, stretchable, twistable andresilient. Thus the structurally stable coating or layer of butadieneacrylonitrile copolymer solvent formerly in tank T as specified inExample 11 and in addition a roll of elastomeric film or tape of thetype alluded to herein is substituted in place of the tape F;Consequently the multiplicity of staple elements SE passing under thewiper block WB will have their upper faces coated by an adhesive coatingor layer and therefore the juxtapositioned lengths thereof areresiliently united or bonded. On passing through the drying chamber TCthe adhesive coating is still not completely dry, although more tacky. Alayer of structurally stable film or tape F is applied to such tackycoating under pressure by roller RR under normal atmospheric andtemperature conditions. The staple element belt or strip formed ispassed on to the conveyor CB and cut to predetermined lengths asdesired. Of course, in all of the examples above alluded to, suchlengths may be severally processed in the companion dies DF and DM toform a U-shaped elastic but deformable staple strip or stack asSS, whichas a unit may be loaded, as is well appreciated, in a conventionalstapling machine. This elastic unit although it may be twisted, flexed,stretched and even have-one part thereof swung to be in superimposedrelation with the remainder of the stack without t destroying itsusefulness since the twisted, stretched or flexed parts thereof retractto their normal position due to the compensatory action of the elasticcoating and elastic tape. This likewise holds true in the case of thestaple element elastic belt herein disclosed. This type of belt or stackmay be subjected to appreciable shock without, however, causing ruptureof any part of the belt or stack. In particular, the unitary stack orcartridge SS may be thrown into the air and allowed to drop even on ahard floor without causing any break in the stack or the staples thereofto scatter.

Where a staple element belt is inserted in a staple machine, at timesstaple elements thereof may be out of line with the remaining parts ofthe belt, causing the foremost staple element to advance obliquelyacross the raceway. This condition may also arise in the case of astaple stack in a stapling machine. By the present invention, even ifthe foremost staple element of a belt or a staple of the stack doestravel across the raceway biased thereto, it will right itselfautomatically when it meets the front wall of the staple raceway due tothe elastic connection between the foremost staple to be severed and thenext succeeding staple of the belt or stack. It therefore follows thatboth of the latter are compensatory to the irregularities in the feed ofthe belt or stack towards the raceway or even in regard to theuncontrollable toler ances in the staple element or staple guide channelof the stapling machine.

In Example III, it has been mentioned that a plastic elastorneric filmor tape F is applied to the wet adhesive resilient coating on thejuxtapositioned staple elements. Manifestly, this tape adds strength tothe elastic coating connection and thus defining with the lattersuperimposed and united elastic continuous or uninterrupted syntheticplastic layers. Apart from providing additional strength, the plasticelastomeric film or tape fully covers the exposed top surface of thecoating C which is merely spread along the central zone area of thestaple elements intermediate the margins M thereof and having a widthsubstantially coextensive with the width of the elastic tape F applied.By using this tape, the thickness of the elastic coating C may bereduced. After application to the coated surface, the tape provides adry and exposed surface, permitting the staple element belt to be rolledor folded cartridge form at once.

Moreover, since the staple elements of the belt are resilient connected,either by the resilient coating alone or by the laminated reinforcedelastic bond defined by resilient coating together with the resilienttape, the elements of the belt are susceptible to lateral displacementrelative to the main body of the belt. that is, to the longitudinal axisof the belt. Obviously, such lateral displacement of the staples ispossible in case of the unitary elastic staple stack. In case of thebelt or the stack, both of the latter are compensatory in thatafterdistortion or lateral offset, either voluntary or involuntary, of a partof the elastic belt or a part of the staple stack, that portion of thebelt or stack previously offset will automatically line up with theraceway in a stapling machine. Also it may be stated that the elasticcoating or adhesive layer and/or the elastomeric film F define flexibleand resilient hinged connections along the fastening element strip.linking adjacent elements of adjacent pairs of elements to permit oneelement of any pair of elements to swing relative to the adjacentelement of its pair to facilitate folding of the staple or fasteningelement strip along any of the hinged connections or permittingconvenient Winding of the strip about one end thereof to define thecompact roll.

Example IV In the case of the but'adiene acrylonit-rile copolymer, thelatter is a sticky and tacky substance providing a highly satisfactoryelastic connection between the staple.

6 no solids after drying. Thusthe dry staple elements SE passing underthroat G are first moistened with toluene. On this wet coating a layerof plastic elastomeric film or tape F of the type alluded to is applied.Toluene softens the film F which incidentally is a polymer. In thiscase, the drying chamber is eliminated but roller RR is heated by anysuitable means. The heated roller in part melts the film or tape F,causing it to 'adhere to the staple elements. The film coating likewiseforms a resilient or elastic structurally stable connection between thepair of elements of the belt. This elastic connection, even though anadhesive coating was not employed, possesses substantially-similarcharacteristics as if an adhesive. coatingwere used, namely, the stapleelement belt formed is flexible in all directions, has elastornericcharacteristics, being deformable, twistiable and even more important,its adhesion to the stapleelernents is greater than its cohesion betweenany two staple elements.

Example vV In this case, wire W prior to being fed into the staplelament forming machine has its surfaces roughened either by sandblasting, etching or knurl-ing in any suitable manner. Tank T and thedrying chambers are elimirrated. A layer of plastic elastomeric film ortape of the type alluded to is fed against the roughened staple elementsand "against the action of the heated roller RR. When heated, theplastic elastomeric film becomes tacky and locks into the roughenedsurfaces. The elastic connection formed possesses similarcharacteristics as pointed out in connection with Example IV.

Example VI CH2 CH2) 4C0 In use of precoated wire, the wiper block WB androller RR are eliminated. The solvent is applied directly to theprecoated staple elements SE.

By such action, the precoated elements are merged or fused together toform a continuous resilent coating or layer. Thereafter if desired, thefused staple elements may be passed through the dryer to acceleratedrying. if the drying chamber be not employed, the precoated Wiresto-aple elements may be fused together under a preheated roller as itwell appreciated. The elastic connection between the staple elementspossess the same property characteristics as pointed out in connectionwith the examples hitherto discussed.

In all the examples described, the staple element belt is elastic andmay be wound closely about itself to leave no axial bore therethrough,that is, even its innermost convolution is substantially at the orgin ofthe cartridge roll formed. Thus the cartridge in the form of 'a roll" orpack occupies a relatively small space although containing if desired,5000 or more staple elements. This may also be said of the cartridge ifthe staple element belt be folded machine gun belt fashion. These typesof elastic staple element cartridges can be conveniently loaded in astaple machine.

For purposes of specification, the expressions, staple element or staplebroadly mean a fastening member adapted to secure parts together. Also'theexpressions stack or pack mean a cartridge, that is, a refill orreplacement for such cartridge. In all the examples described herein,the elastic, deform-able, flexible, stretchable stack or row of stapleswhich constitutes a:

U-shaped cartridge as 55, may be formed in one operation out of theherein disclosed staple element belt wherein each element thereof isappreciably greater in length than its thickness.

The staple elements or members above alluded to in fact are of suitablesteel wire and as a further example they may be preco ated, that is,covered by 'a relatively thin coating of brass, copper or zinc, etc.

As many changes could be made in the embodiments herein disclosed andmany apparently widely different modifications of the invention could bedevised without departing from the scope thereof, it is intended thatall matter contained in the above description or shown in theaccompanying drawings shall be interpreted as illustrative and not in alimiting sense, for example, the expression to the effect that thestaple elements are independent of each other means that such elementsare bodily separate, that is, bodily mutually exclusive of each otherand that such normal disas-sociation exists except by the flexible andfoldable coating C and/or the superimposed fiexible and foldable film Frespectively subsequently applied to the elements and to the coating andrecited in the latter part of the appended claims.

I claim:

1. As a new article of manufacture, a pliable staple element stripcomprising a multiplicity of metal rectilinear staple elements, saidelements of said strip adopted to be formed into U-shaped staples andbeing independent of each other and each being of appreciably greaterlength than its breadth and thickness, adjacent elements of said striphaving their adjacent sides disposed transversely of said strip and injuxtaposition, a thin flexible synthetic plastic layer common and'adhered to adjacent elements of said strip and disposed along theentire length of the latter, said layer having less inherent cohesivestrength than the adhesive bond thereof to said elements, said layerconstituting swinging connections between said adjacent elements of saidstrip, and said swinging connections constituting uninterrupted linkmeans for said adjacent elements to permit twisting of said strip atsaid connections.

2. As a new article of manufacture, a pliable staple element stripcomprising a multiplicity of metal staple elements adapted to be formedinto U-shaped staples, said elements of said strip being alignedsubstantially in the same plane longitudinally of said strip andindependent of each other and each being of appreciably greater lengththan its breadth andthickness, adjacent elements of said strip havingtheir adjacent sides disposed transversely of said strip and injuxtaposition, a thin flexible continuous synthetic plastic resilientlayer adhered to adjacent elements of said strip, said layer having lessinherent cohesive strength than the adhesive bond thereof to saidelements, said layer constituting resiliently swinging connectionsbetween said adjacent. staple elements of said strip, and saidresiliently swinging connections constituting resilient link means forsaid adjacent elements to permit twisting of said strip at saidconnections.

3. As a new article of manufacture, a pliable staple element stripcomprising a multiplicity of metal staple elements adapted to be formedinto U-shaped staples, said elements of said strip being alignedsubstantially in the same plane longitudinally of said strip andindependent of each other and each being of appreciably greater lengththan its breadth and thickness, adjacent elements of said strip havingtheir adjacent sides disposed transversely of said strip and injuxtaposition, a thin flexible continuous synthetic plastic layeradhered to adjacent elements of said strip, said layer having lessinherent cohesive strength than the adhesive bond thereof to saidelements, said layer constituting swinging connections between saidadjacent elements of said strip, and said swinging connectionsconstituting link means for said adjacent elements to permit twisting ofsaid strip at said connections, and in which the plastic of. said layeris a modified copolymer butadiene acrylonitrile rubber.

4. As a new article of manufacture, a pliable staple element stripcomprising a multiplicity of metal staple elements adapted to be formedinto U-shaped staples, said elements of said strip being alignedsubstantially in the same plane longitudinally of said strip andindependent of each other and each being of appreciably greater lengththan its breadth and thickness, adjacent elements of said strip havingtheir adjacent sides disposed transversely of said strip and injuxtaposition, a thin flexible continuous synthetic plastic layeradhered to adjacent elements of said strip, said layer having lessinherent cohesive strength than the adhesive bond thereof to saidelements, said layer constituting swinging connecticns between saidadjacent elements of said strip, and said swinging connectionsconstituting link means for said adjacent elements to permit twisting ofsaid strip at said connections, said plastic layer being. reinforced bya pliable synthetic plastic film superimposed thereon and bondedthereto, the bond of said film to said layer having an adhesive strengthgreater than the cohesive strength of said film.

5. As a new article of manufacture, a pliable and resilient fasteningelement strip comprising a multiplicity of U-shaped metal fasteners,said fasteners of said strip being independent of each other and eachbeing of appreciably greater length than its breadth and thickness,adjacent fasteners of said strip having their adjacent sides disposedtransversely of said strip and in juxtaposition, a thin flexiblecontinuous synthetic plastic resilient layer adhered to adjacentfasteners of said strip, said layer having less inherent cohesivestrength than the adhesive bond thereof to said fasteners, said layerconstituting resiliently swinging connections between said adjacentfasteners of said strip, and said resiliently swinging connectionsconstituting resilient link means for said adjacent fasteners to permittwisting of said strip at said connections.

6. As a new article of manufacture, a pliable fastening clement stripcomprising a multiplicity of U-shaped metal fasteners, said fasteners ofsaid strip being independent of each other and each being of appreciablygreater length than its breadth and thickness, adjacent fasteners ofsaid strip having their adjacent sides disposed transversely of saidstrip and in juxtaposition, a thin flexible continuous synthetic plasticlayer adhered to adjacent fasteners of said strip, said layer havingless inherent cohesive strength than the adhesive bond thereof to saidfasteners, said layer constituting swinging connections between saidadjacent fasteners of said strip, and said swinging connectionsconstituting link means for said adjacent fasteners to permit twistingof said strip at said connections, and in which the plastic of saidlayer is a modified copolymer butadiene acrylo-nitrile rubber.

7. As a new article of manufacture, a pliable fastening element stripcomprising a multiplicity of U-shaped metal fasteners, said fasteners ofsaid strip being independent of each other and each being of appreciablygreater length than its breadth and thickness, adjacent fasteners ofsaid strip having their adjacent sides disposed transversely of saidstrip and in juxtaposition, a thin flexible continuous synthetic plasticlayer adhered to adjacent fasteners of said strip, said layer havingless inherent cohesive strength than the adhesive bond thereof to saidfasteners, said layer constituting swinging connections between saidadjacent fasteners of saidstrip, and said swinging connectionsconstituting link means for said adjacent fasteners to permit twistingof said strip at said connections, said plastic layer being reinforcedby a pliable synthetic plastic film superimposed thereon and bondedthereto, the bond of said film to said layer having an adhesive strengthgreater than the cohesive strength of said film.

(References on following page) 9 References Cited in the file of thispatent UNITED STATES PATENTS Vogel Nov. 22, 1938 Hoffman Nov. 28, 1939 5Bernstein Feb. 25, 1941 Saunders May 22, 1945 Gross Feb. 5, 1946Jennings June 10, 1946 Perkins -2 June 10, 1952 m FOREIGN PATENTS GreatBritain May 28, 1914 Great Britain Mar. 13, 1930 OTHER REFERENCES

